Acyclic diene polycondensation (ADP) of diallyldiorganosilanes (CH2 = CHCH2)(2)SiR2 (where R = Me, Ph), in the presence of various ruthenium and rhodium complexes, led predominantly to linear silylene-propenylene oligomers. Ruthenium catalysts (e.g. RuCl2(PPh3)(3), RuHCl(CO)(PPH3)(3), and RuCl(SiMe3)(CO)( PPh3)(2)) were found to be more efficient than the rhodium ones. The reaction proceeds via preliminary catalytic isomerization of allylsilane to silyl-1-propenes followed by their oligococondensation.